Katy was front row to support her pal as she performed with Calvin Harris at the music festival held in California.

And when RiRi jumped off stage, the pair shared a quick hug before she hopped over into the crowd.

The Umbrella star seems to have taken an aversion to being able to stand on her own feet on stage though, as similar to her other set earlier in the day, she climbed aboard a male pal shoulders to perform, even tweeting a pic of his slaphead between her thighs.

Meanwhile Katy continued in her quest to dye her hair every colour of the rainbow.

She was showing off her new do at the festival, having swapped her electric blue bob for tumbling purple tresses.